1. Field of the Invention
The present invention relates generally to perfluoride processing apparatus and, more particularly, to perfluoride processing apparatus suitable for use during processing of perfluoride-carbon or perfluocarbon (PFC) gases which generate in semiconductor fabrication processes and liquid crystal manufacturing processes or the like.
2. Prior Art
In the semiconductor fabrication and liquid crystal manufacturing processes, PFC gases are used as an etching gas of semiconductor and liquid crystal materials, a cleaning gas of etchers, and a cleaning gas of chemical vapor deposition (CVD) equipment. However, PFC gases are the ones that are extremely significant in an a thermal coefficient to an extent that it is ten thousand to several thousand times greater than that of CO2. From a viewpoint of production efficiency without consumption of a total amount of PFC gas, the currently available semiconductor/liquid-crystal manufacturing processes are designed so that after having consumed 20 to 50% of the gas, the remaining PFC gas is exhausted and drained out of an etcher (or CVD equipment) as an exhaust or waste gas. For the purpose of precluding anathermalization of the Earth, it is required to perform PFC gas decomposition processing to thereby prevent the PFC gas from being released to external environment. Note that representative examples of the PFC gas include, but not limited to, CF4, CHF3, C2F6, C3F8, C4F6, C5F8, NF3, and SF6.
In order to suppress outward release or emission of PFC gases to external environment, it has been known in semiconductor and liquid crystal manufacturing industries that as disclosed in Japanese Application Patent Laid-Open Publication No. Hei 11-319485, perfluocarbon decomposition devices (referred to as PFC decomposition devices hereinafter) are installed in units of PFC gas-use etchers so that each is adjacent to its associated etcher, wherein a catalyst is used to perform decomposition processing of a PFC gas in exhaust gases as drained out of the etchers. This PFC decomposition device is equipped with a reaction unit which is filled with a PFC decomposing catalyst, a silicon component removing device which removes silicon components contained in an exhaust gas to be supplied to the reaction unit, a cooling chamber for cooling or refrigerating the exhaust gas that contains therein decomposition gas of the PFC as decomposed by the catalyst, and further an acidic gas removing device for removing an acidic gas contained in the exhaust gas as drained out of the cooling chamber. A catalyst-using PFC decomposition device is also disclosed in Japanese Application Patent Laid-Open Publication No. Hei 11-70322.
As the silicon component removing device, the cooling chamber and the acidic gas removing device require the use of water, it is a must to connect a water supply pipe to the individual PFC decomposition device. In view of the fact that each PFC decomposition device is installed within a clean room, respective water supply pipes being connected to them also are installed in the clean room. Water drain pipes also are connected to the PFC decomposition devices respectively. Due to this, part of the inner space of the clean room is to be occupied by the respective PFC decomposition devices and the water supply/drain pipes associated therewith. In case a clean room is newly formed with semiconductor fabrication apparatus (or alternatively liquid crystal manufacturing apparatus) such as a plurality of etchers installed together therein, a need is felt to acquire within the clean room an installation space of a plurality of PFC decomposition devices and a variety of types of utility equipment (such as water supply pipes and water drain pipes or the like) associated therewith, which would result in the space within the clean room being enlarged accordingly. Alternatively, in the case of installation of one or more PFC decomposition devices within the currently established clean room, it sometimes happen that the semiconductor fabrication apparatus (or liquid crystal manufacturing apparatus) such as etchers which have been installed within the clean room must be moved in order to acquire the installation space of the PFC decomposition devices and various types of utility equipment.
Because of the installation of a variety of types of utility equipment with respect to each PFC decomposition device within the clean room, it takes much time to install these facilities.